DAVID Cameron has admitted he is powerless to bypass the Lib Dems and introduce Government legislation guaranteeing a European Union referendum in the next Parliament.

The stark declaration, revealed in a private letter to Conservative MPs, comes despite Mr Cameron insisting only days ago that he would consider the introduction of legislation paving the way for a vote on Europe after the next election.

In the letter, Mr Cameron admitted that his Coalition deal with the pro-European Liberal Democrats means the Government cannot introduce the legislation which could ultimately result in a vote on Europe.

Mr Cameron has promised to hold a referendum on the UK relationship with the EU in the next Parliament, if he is re-elected.

"This Government’s legislative programme is founded on the Coalition Agreement which did not include legislating in this Parliament for an In-Out referendum," Mr Cameron wrote.

“For the Government to be able to bring forward the type of legislation you propose, we would require the agreement of our Coalition partners which, as things stand, is not forthcoming.”

The admissision is sure to spark outrage from frustrated voters who made their feelings about a referendum clear in a recent poll.

In the survey, the majority of Britons revealed that they want either a completely new relationship with the EU or to leave altogether.

Forty-two per cent of voters said that they wanted a relationship based on free trade and little else while 21 per cent called for British withdrawal, according to the YouGov poll.

If there was an in-out referendum tomorrow, 46 per cent said they would vote to quit the EU against 35 per cent who would vote to stay in.

The majority of British voters have backed bids for an EU referendum

We would require the agreement of our Coalition partners

David Cameron

In a bleak sign that British voters have lost faith in the Prime Minister, more than half (53 per cent) said that they believe Mr Cameron's assertion that he will secure substantial changes with the EU is meaningless.

One angry signatory to the letter voiced his frustration at the Prime Minister’s apparent shift of position from his pre-election comments.

“This is exactly why we’re in this state: people don’t believe him when he says these things, because he always weasels out of his promises,” the MP said. “There’s no authenticity.”

With many voters losing faith in Mr Cameron’s pledge, the UK Independence Party has seen a surge in support from Tory defectors.

The fierce Conservative debate over Europe has intensified this week after Lord Lawson of Blaby, a former Chancellor, also backed demands that Britain should now leave the EU.